Marco,
Now that you have the complete information, any idea why the Collection Variables are unviewble? These are simple collection variables of scalar type - the ones that the PL/SQL developer supports.
I have been debugging why PL/SQL developer does not show the Collection Variable properly when it used to do so quite some time back. This is what I get in my Tools->Sessions which I map to V$_SQLTEXT:
declare runtime_info sys.dbms_debug.runtime_info;
begin sys.
dbms_debug.default_timeout :=...
The problem can be narrowed down to Oracle 9.2.0.1 specifically since none of the older and newer versions of PL/SQL developer now work for "View Collection" option. And before we migrated from Oracle 8.xx to 9.2, atleast the older versions of PL/SQL developer *were* working correctly. Any clues...
I am also facing this problem which is seriously affecting my developement since the entire code is based on collections.
The "View Collection Variable" option used to work just fine till we upgraded our server from 8.1.7 to 9.2.0.4. Simultaneously I moved from Windows/2000 to XP.
Since then...